In recent years, input apparatus such as operation units, switches and the like having touch sensors such as touch panels, touch switches and the like to receive input operations by users have been widely used for mobile terminals such as mobile phones and gaming machines, information equipment such as calculators and ticket vending machines, home electric appliances such as microwaves, TV sets and lighting equipment, industrial equipment (FA equipment) and the like.
There are known a variety of types of the touch sensors, such as a resistive film type, a capacitive type, an optical type and the like. However, touch sensors of these types receive a touch input (input operation) by a pressing object (pressing means) such as a finger or a stylus pen and, unlike push-button switches, the touch sensors themselves are not physically displaced when being touched.
As such, there is suggested an input apparatus, for example, which has a control unit which monitors an operation to the touch sensor and, when an input is detected, drives a speaker to generate a confirmation sound such that feedback of the input operation is provided (for example, see Patent Document 1). There are also suggested input apparatuses having a control unit which monitors an input to the touch sensor and, when the input is detected, drives a piezoelectric element via a piezoelectric element control unit to vibrate the touch sensor such that a tactile sensation is provided as feedback at operator's fingertip (for example, see Patent Documents 2, 3).